The invention relates to a connector system with a coupling system and a port system for coupling flexible tubing to a container containing medicinal liquids.
DE-A-197 17 765 describes a sterile connector system for linking flexible tubing to a foil bag or tank containing a medicinal liquid. The known connector system is comprised of a coupler or port system which is equipped with a channel-type cavity and which is sealed by a pierce-through diaphragm. The coupler is comprised of a lower base part that can be welded to the bag and a tubular upper part (connector) for accommodating the puncturing boss (spike), at which the flexible tubing is attached. A sterile connector system as described in the foregoing is also described in DE-A-196 37 856.
The known connector systems have been successful in practical applications. It is a disadvantage, however, that the spike, prior to its connection to the bag, is exposed to the non-sterile environment. Caps or similar contrivances are common as closing elements; however, their disadvantage is the fact that they must be removed before insertion of the spike into the connecter, whereby the spike is unprotected when being inserted.
PCT96/00093 describes a connector system in which the spike is enclosed by a flexible hose which is fastened to the tubular upper part (connector) of the coupler by means of a coupling nut. For the purpose of creating the fluid connection, the spike is screwed into the tubular upper part of the coupler, whereby the diaphragm obturating the upper part is pierced. The disadvantage is that the maximal extensibility and deformability of the hose limits the clearance range of the spike. This is a disadvantage inasmuch as a diaphragm situated deep in the connector and which is sufficiently touch-protected can be penetrated by the spike only if the spike is inserted deeply into the connector, which makes handling more difficult. Moreover, there is the risk that the flexible hose may tear, resulting in system leakage. Furthermore, drawing the flexible hose onto the spike makes the creation of the connector system more difficult. From the point of view of waste management, it is also a disadvantage that the connector is made of different materials.
Therefore the object of the present invention is to provide an easy-to-use and inexpensive connector system that is easy to manufacture and whose spike is adequately touch-protected when being connected to the tank or bag.
This problem is solved by a connector system having a coupling system and a port system constructed according to the principals of the present invention.
A spike of the coupling system of the present invention is enveloped along its entire length by a spike sheath which has a first part and a second part. The first part and the second part can be screwed into each other in order to telescopically elongate or shorten the spike sheath. To accomplish this, the first part can be provided either with an internal threading and the second part with an external threading or the first part with an external threading and the second part with an internal threading. The second part of the spike sheath can be coupled to a connector of the port system.
For coupling the spike to the port system, the spike sheath is connected to the connector of the port system. Then, for shortening the spike sheath axially, the first part is screwed completely onto or into the second part, whereby the spike pierces a diaphragm of the port system and so establishes the fluid connection. In so doing, the spike is protected from contact.
In one preferred embodiment of the invention, the diaphragm is a foil situated on the underside of a base element of the port system. The pierce-through diaphragm can also be a foil situated between the connector and the base element. In lieu of a foil, flat plastic laminate or similar material, which is one piece with the port system, may be used as the diaphragm. The deeper the diaphragm lies, the longer the first part and the second part of the spike sheath must be. Using a diaphragm that is situated higher, the axial length of the spike sheath can thus be shortened. Compact construction with satisfactory touch-protection results if the diaphragm is situated in the middle of the channel-type cavity of the port system.
The second part of the spike sheath is appropriately screwed onto the connector of the port system. In order to screwably attach the second part to the connector, the connector is provided with an external screw thread and the second part is provided with an internal screw thread. In lieu of a screw connection, a bayonet fastening or similar system can be used.
In another preferred embodiment of the invention, the second part of the spike sheath forms a stop for the first part in which the second part consists of two sections with different diameters. For consistent securing of the two parts of the spike sheath, a threaded stop can be provided. In addition, the first part should be fastened securely to the spike.
In order to assure that the spike does not co-rotate on connection to the port system, a guide piece is advantageously provided on the connector and the spike pushed into it to prevent rotation or swiveling.
An alternative embodiment of the connector system eliminates the telescopic extension of the spike sheath. The spike sheath is a union nut which extends beyond the tip of the spike such that the spike is enveloped over its entire length. In this embodiment, the diaphragm is not in the base element or between the insert base element and the connector, but is situated in the connector of the port system, such that the spike can pierce through the diaphragm when the spike sheath is screwed on.